Selective harvester

ABSTRACT

The present application relates to selective harvesting of agricultural objects, such as asparagus spears. One described example relates to a harvester that includes at least one set of independently controllable cutter arm assemblies that rotate about a common axis to harvest individual asparagus spears.

PRIORITY

This patent application is a Continuation of and claims priority fromU.S. Utility Application No. 12/789,402 filed on May 27, 2010 which is anon-provisional application that claims priority from U.S. ProvisionalApplication No. 61/183,014, filed on Jun. 1, 2009. This patentapplication is related to co-pending U.S. Utility Application No.12/789,410 filed on May 27, 2010. Each of these applications areincorporated by reference herein in their entirety.

BACKGROUND

Many agricultural crops lend themselves to a single harvest per season.For instance grain crops, such as corn and wheat, can be harvested allat once. For these crops, mechanical harvesters, such as combines canmake a single pass over the ground and harvest the year's crop. Othercrops, such as asparagus, do not lend themselves to single passharvesting. Instead these crops produce better yields when individualfruits or plants are selectively harvested at an appropriate conditionfor market. After a period of time, another pass can be made over theground to harvest additional fruits or plants that are now ready forharvest. This process can be repeated until the season's harvest iscompleted.

For these types of crops, one aspect of profitability for the grower isto selectively harvest the market ready plants or fruits with as littledamage as practicable to the remaining fruits or plants. Stated anotherway, one harvesting criteria is to successfully harvest as many of themarket-ready plants as possible. Another harvest criteria is to reducecollateral damage to the remaining immature plants.

Despite many attempts, mechanical selective harvesting of many of thesecrops, such as asparagus, has remained elusive. This is borne-out inthat the vast majority of crops, such as asparagus, continue to bepicked manually. Manual picking is very expensive and often exceedsone-half of the value of the crop to the grower. Further, manuallyharvesting asparagus is grueling work and is generally performed byseasonal workers. Because of the nature of the work, workers oftenchoose other agricultural work instead of asparagus harvesting. As aresult, crops risk going unharvested. Accordingly, growers tend to bereluctant about planting acreage in asparagus. In summary, despite greateconomic incentive and decades of attempts, no viable selectiveharvesters have been developed. The present inventive concepts addressthese and other issues.

SUMMARY

The described implementations relate to selective harvesting ofagricultural crops. One implementation relates to an asparagus harvesterthat can have one or more sets of independently controllable cutter armassemblies. The cutter arm assemblies can rotate about a common axis toharvest individual asparagus spears. Various other inventive aspects aredescribed below.

The above listed examples are intended to provide a quick reference toaid the reader and are not intended to define the scope of the conceptsdescribed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate implementations of the conceptsconveyed in the present application. Features of the illustratedimplementations can be more readily understood by reference to thefollowing description taken in conjunction with the accompanyingdrawings. Like reference numbers in the various drawings are usedwherever feasible to indicate like elements. Further, the left-mostnumeral of each reference number conveys the figure and associateddiscussion where the reference number is first introduced wherefeasible.

FIG. 1 shows a perspective view of a selective harvester in accordancewith some implementations of the present concepts.

FIGS. 2-3 show elevational views of selective harvester components,namely a harvester apparatus in accordance with some implementations ofthe present concepts.

FIG. 4 shows an exploded perspective view of the harvester apparatusshown in FIGS. 2-3.

FIGS. 5-6 show elevational views of harvester apparatus components inaccordance with some implementations of the present concepts.

FIG. 7 shows a perspective view of the harvester apparatus componentsshown in FIGS. 5-6.

FIG. 8 shows an exploded perspective view of the harvester apparatuscomponents shown in FIGS. 5-6.

FIG. 9 shows an elevational view of harvester apparatus components inaccordance with some implementations of the present concepts.

FIG. 10 shows an exploded perspective view of the harvester apparatuscomponents of FIG. 9.

FIG. 11 shows an elevational view of harvester apparatus components inaccordance with some implementations of the present concepts.

FIG. 12 shows an exploded perspective view of the harvester apparatuscomponents of FIG. 11.

FIGS. 13-16 show elevational views of harvester apparatus components inaccordance with some implementations of the present concepts.

FIG. 17 shows an exploded perspective view of the harvester apparatuscomponents of FIGS. 13-16.

FIGS. 18-20 show elevational views of harvester apparatus components inaccordance with some implementations of the present concepts.

FIG. 21 shows an exploded perspective view of the harvester apparatuscomponents of FIGS. 18-20.

FIGS. 22-24 show elevational views of harvester apparatus components inaccordance with some implementations of the present concepts.

FIG. 25 shows a perspective view of the harvester apparatus componentsof FIGS. 22-24.

FIG. 26 shows an exploded perspective view of the harvester apparatuscomponents of FIGS. 22-24.

FIGS. 27-28 show elevational views of harvester apparatus components inaccordance with some implementations of the present concepts.

FIG. 29 shows an exploded perspective view of the harvester apparatuscomponents of FIGS. 27-28.

FIGS. 30-31 show elevational views of harvester apparatus components inaccordance with some implementations of the present concepts.

FIG. 32 shows a perspective view of the harvester apparatus componentsof FIGS. 30-31.

FIG. 33 shows an exploded perspective view of the harvester apparatuscomponents of FIGS. 30-31.

FIG. 34 shows a sectional view of the harvester apparatus components inaccordance with some implementations of the present concepts.

FIG. 35 shows an elevational view of the harvester apparatus componentsof FIGS. 30-31.

FIG. 36 shows an exploded perspective view of the harvester apparatuscomponents of FIGS. 34-35.

FIG. 37 shows an elevational view of harvester apparatus components inaccordance with some implementations of the present concepts.

FIG. 38 shows an exploded perspective view of the harvester apparatuscomponents of FIG. 37.

FIGS. 39-40 show elevational views of harvester apparatus components inaccordance with some implementations of the present concepts.

FIG. 41 shows an exploded perspective view of the harvester apparatuscomponents of FIGS. 39-40.

FIGS. 42-91 show further views of the harvester apparatus components invarious relative positions in accordance with some implementations ofthe present concepts.

FIG. 92 shows a sectional view of harvester apparatus components inaccordance with some implementations of the present concepts.

FIGS. 93-95 show elevational views of harvester apparatus components inaccordance with some implementations of the present concepts.

DETAILED DESCRIPTION

Overview

This patent application pertains to selective harvesting of agriculturalcrops, such as asparagus. In one case, the selective harvesting can beaccomplished via a harvesting machine or “selective harvester”. Theselective harvester can pass over a swath of land and selectivelyharvest individual agricultural objects, such as market-ready asparagusspears, while leaving immature spears to continue growing.

In some cases, the selective harvester can include a plurality ofindependently controllable harvesting apparatus that can be collectivelyarranged to harvest spears as the harvester travels over the swath ofland. Individual harvesting apparatus can include a set of independentlycontrollable cutter arm assemblies and a control mechanism forcontrolling the cutter arm assemblies.

Briefly, the harvesting apparatus can be maintained in a ready positionabove the agricultural crops to avoid damaging the asparagus plants.When market-ready asparagus spears are sensed, the control mechanism cancause an individual cutter arm assembly to rotate radially downward toharvest the asparagus spear and then return to the ready position toreduce damaging other spears.

Harvester Examples

FIG. 1 offers an example of a selective harvester 100. The harvester canmove in a direction of travel indicated at 102 to selectively harvestasparagus spears along a width indicated at 104. In this case, theharvester is defined by a pair of backbone structures 106(1) and 106(2).One or more structural components can extend between the backbonestructures 106(1), 106(2) to maintain a constant distance therebetween.In this particular configuration three structural components areutilized. For descriptive purposes, these structural components areidentified as front structural component 108(1), middle structuralcomponent 108(2) and rear structural component 108(3). Front wheels110(1) and 110(2) are secured to front portions of the backbonestructures 106(1) and 106(2), respectively. Similarly, rear wheels112(1) and 112(2) are secured to rear portions of the backbonestructures 106(1) and 106(2), respectively. Steering of the harvester100 can be achieved via the front and/or rear wheels.

In this implementation, selective harvester 100 can be leveled relativeto the xyz reference axes during use by controlling two pair ofhydraulic cylinders. The first pair of hydraulic cylinders 114(1) and114(2) are connected between front portions of backbone structures106(1) and 106(2) and front wheel 110(1) and 110(2) via parallellinkages 116(1) and 116(2), respectively. The second pair of hydrauliccylinders 118(1) and 118(2) are connected between rear portions ofbackbone structures 106(1) and 106(2) and rear wheels 112(1) and 112(2),respectively. Hydraulic cylinders 114(1), 114(2), 118(1) and 118(2) canbe independently controlled via a valve bank (not shown) that isconnected to an orientation sensor(s) (not shown), such as a gyroscope,camera, and/or ultrasonic sensor.

In this case, a cutter shaft 120 extends between backbone structures106(1) and 106(2). A plurality of harvesting apparatus 122 arepositioned on cutter shaft 120 and supported from middle structuralcomponent 108(2). Supporting the harvesting apparatus 122 from thestructural component can reduce or avoid flexing and/or sagging ofcutter shaft 120. For instance, in some implementations, at least 50%and in some cases more than 90% of the weight of the harvestingapparatus can be supported by the structural component rather than thecutter shaft.

In this particular implementation, the selective harvester 100 isconfigured to utilize 32 harvesting apparatuses 122. However, to allowvisualization of the cutter shaft 120, only harvesting apparatuses122(16)-122(18) are visualized (i.e., 122(1)-122(15) and 122(19)-122(32)are removed in FIG. 1). As is illustrated relative to harvestingapparatus 122(18), an individual harvesting apparatus can selectivelyharvest asparagus spears along a width w₁. Collectively, the pluralityof harvesting apparatus 122 can harvest the entire harvest widthindicated at 104. Of course, the illustrated number of harvestingapparatuses and/or sensors is provided for discussion purposes and isnot critical. Other implementations can use more or less harvestingapparatuses and/or sensors than the illustrated configuration.

One or more sensors 126 can be utilized to detect asparagus spears alongthe harvest width 104 as the harvester moves in the direction of travel102. In this implementation, there are 32 sensors 126(1)-126(32) (notall of which are designated with specificity). The sensors cancollectively sense harvest width 104. In this case, individual sensorsare in a one-to-one relationship with individual harvesting apparatus122. For instance, sensor 126(18) works cooperatively with harvestingapparatus 122(18).

In this case, an individual sensor, such as sensor 126(18) can sense awidth w₂ that corresponds to a harvest width w₁ of an individualharvesting apparatus 122(18). Thus, when extended in the direction oftravel, widths w₁ and w₂ can define a harvest zone 130(18) for anindividual harvesting apparatus 122(18) and corresponding sensor126(18).

The sensors can detect individual spears and determine whether adetected spear satisfies one or more harvest parameters, such as spearheight and/or diameter. In one example, the harvest parameters can beselected to determine whether individual spears are market ready. Uponsensing a spear that satisfies the harvest parameter(s), an individualsensor (such as sensor 126(18)) can generate a signal that causes anindividual harvesting apparatus (such as harvesting apparatus 122(18))to harvest an individual sensed spear. This process will be described inmore detail below relative to FIG. 2. Note, at this point in thedescription that, in some harvester configurations, a distance 132 inthe x-direction between the sensors (such as sensor 126(18)) andharvesting apparatuses (such as harvesting apparatus 122(18)) is knownand utilized to coordinate the selective harvesting.

As mentioned above, this particular configuration employs a sensor 126for each harvesting apparatus 122 in a one-to-one relationship with 32sensors and 32 harvesting apparatuses. For example, sensor 126(18) cansense harvest zone 130(18). Harvest zone 130(18) corresponds to width w₁so that as the selective harvester 100 moves along the direction oftravel 102, spears sensed in harvest zone 130(18) pass within width w₁for harvest by harvesting apparatus 122(18). Other implementations canuse a different configuration, such as a common sensor that sensesharvest width 104 and maps to an individual aligned harvesting apparatus122.

Selective harvester 100 can include a power or drive unit 134 forpropelling the harvester and/or for turning cutter shaft 120. Otherimplementations may pull or push the harvester with a tractor or othermechanism and/or turn cutter shaft 120 by connecting a power take off(PTO) shaft to the harvester's cutter shaft.

In summary, selective harvester 100 can move along direction of travel102 to selectively harvest encountered asparagus spears. For purposes ofexplanation, three asparagus spears 134(1), 134(2), and 134(3) areshown. Assume that asparagus spears 134(1) and 134(2) are aligned withharvester apparatus 122(18) (i.e., are within harvest zone 130(18)).Assume further that asparagus spear 134(3) falls within another harvestzone that is not called out with specificity but that asparagus spear134(3) can be simultaneously handled in a similar manner to asparagusspears 134(1) and 134(2). As the selective harvester moves forward,asparagus spear 134(1) can pass proximate sensor 126(18) (and/or asensing region). Assume that asparagus spear 134(1) satisfies theharvest parameters described above. In such a case, a signal can be sentto harvest apparatus 122(18) to cause the harvesting apparatus toharvest asparagus spear 134(1). For instance, if the selectiveharvester's speed along the direction of travel 102 is relativelyconstant and known, then harvesting apparatus 122(18) can pass overasparagus spear 134(1) at a subsequent time Δt after sensor 126(18).Harvesting apparatus 122(18) can be configured to grasp asparagus spear134(1), cut it and lift it away from the ground for further processing.Assume further, that asparagus spear 134(2) is sensed by sensor 126(18)but does not satisfy the harvest parameter(s). In this case, a harvestsignal is not sent to harvesting apparatus 122(18) and the harvestingapparatus (and the overall selective harvester) can pass over asparagusspear 134(2) in a manner that leaves the asparagus spear relativelyunharmed. This configuration can allow asparagus spear 134(2) tocontinue to grow and to potentially be harvested in a subsequent pass bythe selective harvester 100, such as a couple of days later. The sameprocesses can simultaneously occur for asparagus spear 134(3) and otherspears along the harvest width 104.

Specific harvester components are discussed in more detail below. Thesecomponents can be manufactured from materials utilized in otheragricultural machinery such as wheat combines and corn combines, amongothers. Metals can be utilized for many components, but other materials,such as polymers and composites, can be employed.

Harvesting Apparatus Examples

FIGS. 2-4 collectively illustrate harvesting apparatus 122(18) in moredetail. FIG. 2 is a side elevational view (i.e., transverse cutter shaft120 of FIG. 1). FIG. 3 is a front elevational view (i.e., parallel thecutter shaft 120). FIG. 4 is a perspective view that is exploded alongthe cutter shaft 120. In this case, the harvesting apparatus includes adrive wheel assembly 202, a hanger-ring gear assembly 204, an actuatorassembly 206, and a plurality of cutter arm assemblies 208. In thisexample, the harvesting apparatus includes five cutter arm assemblies208(1), 208(2), 208(3), 208(4), and 208(5). Other implementations caninclude more or less cutter arm assemblies. For ease of reference, thehanger-ring gear assembly 204 can be thought of as including a hangerassembly 210 and a ring gear assembly 212.

FIG. 4 shows the relative order of the components as they are positionedon the cutting shaft 120. In this case, the hanger-ring gear assembly204 is positioned on the cutter shaft followed by the cutter armassemblies 208, the drive wheel assembly 202, and the actuator assembly206. The components are then repeated for harvesting apparatus 122(17).

Ring Gear Assembly Examples

FIGS. 5-8 collectively illustrate ring gear assembly 212 in more detail.FIG. 5 is a side elevational view. FIG. 6 is a front elevational view.FIG. 7 is a perspective view. FIG. 8 is a perspective view that issimilar to the view of FIG. 7 but that is exploded along the cuttershaft.

In this example, ring gear assembly 212 includes a cam mounting plate502, a cam 504, a set of eight ring gear mounts 506 (not all of whichare designated with specificity), ring gear 508, ring gear mountingstandoffs 510(1)-510(2), front and rear bumper mount assemblies 512(1)and 512(2), and a shock absorber assembly 514 that includes a shockabsorber piston 515. The ring gear assembly 212 further includes brakeor brake rail 516, long ring gear mounting standoffs 518, a locking cam520, a locking cam plate 522, hanger mount screws 524(1)-524(2), twohanger mount nuts 526, a set of fasteners, such as rivets 528 (not allof which are designated with specificity), a set of fasteners 530 thatin this case entails six screws, a drive wheel hub assembly 532, a setof fasteners 534 in the form of three screws, a set of two fasteners inthe form of screws 536(1) and 536(2), another set of fasteners embodiedas two screws 538(1) and 538(2), two nuts 540(1) and 540(2) and anotherset of fasteners 542 in the form of rivets (not all components can beevidenced in each view).

Note that ring gear 508 is not continuous (i.e., it is circular, butdoes not complete an entire circle). Instead, ring gear 508 defines agap 544. This gap is occupied by, and in some sense selectivelycompleted by a timing gear, an advancing gear, and a trigger tooth thatare introduced below relative to FIGS. 11-12.

While it is somewhat difficult to appreciate from FIGS. 5-8, asindicated in FIG. 5, cam 504 includes a first region indicated generallyat 546 that has a medium thickness T₁. Moving counter-clockwise, the camexpands to a second region indicated generally at 548 that has a greaterthickness T₂, then to a third region indicated generally at 550 that hasa narrow thickness T₃. Continuing in the counter-clockwise direction,the cam again expands in a fourth region indicated generally at 552 thathas a thickness T₄ that is similar to thickness T₂. Finally, the camreturns to thickness T₁ and first region 546. Here, thicknesses T₁-T₄are measured parallel to the xz-plane. These thicker and narrow regionscan provide a camming action as will be explained below relative toFIGS. 56-67.

Hanger Assembly Examples

FIGS. 9-10 collectively illustrate hanger assembly 210 in more detail.FIG. 9 is a side elevational view. FIG. 10 is a perspective view that isexploded along the cutter shaft.

Hanger assembly 210 includes hanger 902, a hanger top edge 904, atrigger ratchet 906, a solenoid assembly 908, a set of trigger ratchetfasteners 910 in the form of three screws, two hanger mount nuts 912(1)and 912(2) for receiving two solenoid mount-hanger bolts 914(1) and914(2), a hanger rubber bumper 916, a top hanger clip 918, a nut 920,and a dust shield sheet metal (not shown).

Hanger 902 can also include a groove, channel or recess 922 along whicha wire(s) can be run to connect solenoid assembly 908 and sensor122(18)(FIG. 1). Further, in this case, trigger ratchet 906 forms fourlatch detents 922(1), 922(2), 922(3), and 922(4).

Actuator Assembly Examples

FIGS. 11-12 collectively illustrate actuator assembly 206 in moredetail. FIG. 11 is a side elevational view. FIG. 12 is an explodedperspective view. In this case, actuator assembly 206 includes anactuator lever ‘part a’ 1102, an actuator lever ‘part b’ 1104, anadvancing gear 1106, an actuator lever ‘part c’ 1108, a shock absorberstriker mount 1110, two trigger bearing fasteners 1114(1) and 1114(2), afastener 1116, two fasteners 1118, two fasteners 1120(1) and 1120(2),three fasteners 1122(1), 1122(2), and 1122(3), a timing gear 1124, twoactuator spacer washers 1126(1) and 1126(2), a trigger 1128, two triggermounting links 1130(1) and 1130(2), two trigger mounting link keepers1132(1) and 1132(2), a trigger wear insert or trigger block 1134, atrigger tooth 1136, and a trigger mounting link plate 1138. While notreadily apparent from FIGS. 11-12, when assembled, actuator lever ‘partb’ 1104 is interposed between trigger block 1134 and trigger tooth 1136.

It is worth noting that timing gear 1124 includes geared regions1140(1), 1140(2), 1140(3), and 1140(4) which are interspaced withgearless regions 1142(1), 1142(2), and 1142(3) (due to space constraintson the drawing page some of these geared and gearless regions aredesignated on FIG. 12 while others are designated on FIG. 11). There isalso a gap or space 1144 between advancing gear 1106 and timing gear1124. These features will be discussed in more below relative to FIGS.42-55.

Cutter Arm Assembly Examples

FIGS. 13-17 collectively illustrate cutter arm assembly 208(1) in moredetail. FIG. 13 is a front elevational view. FIGS. 14-15 are opposingside elevational views of the cutter arm assembly taken transverse thecutter shaft. FIG. 16 is a rear elevational view. FIG. 17 is an explodedperspective view of the cutter arm assembly.

In this case, the cutter arm assembly 208(1) includes a cutter arm mountmaster 1302, a cutter assembly 1304, a spring arm assembly 1306, a camfollower assembly 1308, a trigger pin assembly 1310, a planetary gearassembly 1312, an opening wedge 1314, an arm adjustment set screw 1316,a hex nut 1318, and a closing or locking wedge 1320. The cutter armassembly also includes a push rod 1321 that includes a ball end linkage1322 and a ball end linkage bottom 1324. The cutter arm assembly alsoincludes a rubber bumper or trailing side cutter arm bumper 1326, and afront or leading side cutter arm bumper 1327 (due to space constraintson FIG. 17, leading side cutter arm bumper 1327 is designated on FIGS.14 and 15, but not on FIG. 17). Cutter arm assembly 208(1) also includesfour nyliner bushings 1328 (only two of which are designated withspecificity due to constraints of the drawing page), a cutter arm hubend 1330, a cutter arm bearing key 1332, two fasteners 1334, such as hexhead bolts, a cutter arm angle limit bolt 1336, a screw 1338, and ascrew 1340.

As will be described in more detail below, opening wedge 1314 can engagea contact structure 1341 of cutter assembly 1304 to cause movement ofthe cutter assembly. While it may not be readily apparent from FIGS.13-17, opening wedge 1314 defines a socket configured to receive andretain, the ‘ball’ of ball end linkage bottom 1324. A similar socket inthe cam follower assembly 1308 for receiving the ball end linkage 1322is illustrated in FIG. 29. The cam follower assembly 1308 is discussedin more detail below relative to FIGS. 27-29. Briefly, the cam followerassembly includes a cam follower 1342. Other components of the camfollower assembly are discussed relative to FIGS. 27-29.

Similarly, for discussion purposes here, spring arm assembly 1306 isidentified as including an opening bearing 1344. The spring arm assemblyis discussed in more detail relative to FIGS. 22-26.

Cutter Assembly Examples

FIGS. 18-21 collectively illustrate cutter assembly 1304 in more detail.FIG. 18 is a side elevational view of the cutter assembly. FIGS. 19-20are opposing front and rear elevational views of the cutter assembly.FIG. 21 is an exploded perspective view of the cutter assembly.

In this implementation, cutter assembly 1304 includes a cutter arm 1802,a pad spacer washer 1804, a knife 1806, a pad mounting bracket 1808, twoknife links 1810, a cutter arm spring 1812, two knife washers 1814, fourcountersunk flange nuts 1816, two screws 1818, two long knife link bolts1820, a cutter arm closing spring dowel pin 1822, a cutter arm springbushing 1824, a screw 1826, a retainer 1828, and a pad 1830.

Spring Arm Assembly Examples

FIGS. 22-26 collectively illustrate spring arm assembly 1306 in moredetail. FIG. 22 is a side elevational view. FIGS. 23 and 24 are opposingfront and rear elevational views of the spring arm assembly. FIG. 25 isa perspective view of the spring arm assembly. FIG. 26 is an explodedperspective view of the spring arm assembly.

In this case, the spring arm assembly 1306 includes a left arm 2202, aleft arm spring plate 2204, a button head 2206, an eccentric bearingmount T-nut 2208, opening bearing 1344, locking bearing 1346, aseparator arm 2214, pad 2216, pad 2218, pad mounting bracket 2220,locking bearing washer 2226, opening bearing washer 2228, a spring armpad screw 2232, a screw 2236, a screw 2238, and two hex bolts 2240. Thespring arm assembly also includes the cutter arm closing spring dowelpin 1822, cutter arm spring bushing 1824, and retainer 1828 which wereintroduced above relative to FIGS. 18-21.

Cam Follower Assembly Examples

FIGS. 27-29 collectively illustrate cam follower assembly 1308 in moredetail. FIG. 27 is a side elevational view. FIG. 28 is a frontelevational view of the cam follower assembly. FIG. 29 is an explodedperspective view of the cam follower assembly.

In this implementation, the cam follower assembly 1308 includes twocenter bearing cam followers 2702(1) and 270(2), a modified shoulderbolt trigger pin 2704, a modified washer 2706, a cam follower 1342, acam follower sleeve 2710, a snap ring 2712, a cam follower arm bearingwasher/spacer 2714, a cam follower nut 2716, a socket clamp 2718, and acam follower arm new degree 2720. The cam follower assembly 1308 alsodefines a socket 2722 that is configured to receive ball end linkage1322 (see FIG. 17).

Trigger Pin Assembly Examples

FIGS. 30-33 collectively illustrate trigger pin assembly 1310 in moredetail. FIG. 30 is a side elevational view of the trigger pin assembly.FIG. 31 is a front elevational view. FIG. 32 is a perspective view. FIG.33 is an exploded perspective view of the trigger pin assembly.

In this case, trigger pin assembly 1310 includes a trigger pin housing3002, a trigger pin 3004, two trigger pin bearings 3006(1) and 3006(2),and an internal snap ring 3008.

Planetary Gear Assembly Examples

FIGS. 34-36 collectively illustrate planetary gear assembly 1312 in moredetail. FIG. 34 is a side elevational view of the planetary gearassembly. FIG. 35 is a front elevational view. FIG. 36 is an explodedperspective view of the planetary gear assembly.

In this case, planetary gear assembly 1312 includes a planetary gear3402, two bearing models 3404(1) and 3404(2), a planetary gear stud3406, a T-nut planetary gear 3408, a planetary gear washer 3410, and aplanetary gear nut 3412. Further, planetary gear 3402 can be thought ofas including a toothed or geared portion 3414 and a smooth brake portion3416. As will be described in more detail below relative to FIGS. 42-55,the geared portion is configured to engage the ring gear 508 and thebreak portion is configured to engage brake rail 516 (see FIGS. 6-8).Specifically, break portion 3416 defines a circumferential surface 3418for contacting break rail 516.

Drive Wheel Hub Assembly Examples

FIGS. 37-38 collectively illustrate drive wheel assembly 532 in moredetail. FIG. 37 is a side elevational view of the drive wheel hubassembly. FIG. 38 is an exploded perspective view.

In this case, drive wheel hub assembly 532 includes five cutter assemblybearings 3704(1)-3704(5), four bearing spacer washer bokers3706(1)-3706(4), a front shaft bearing 3708, two shaft bearing IKS3710(1)-3710(2), a trigger arm bearing 3712, a retainer ring smalley3714, a cutter arm hub 3716, and a retainer ring smalley 3718.Individual bearings 3704(1)-3704(5) receive individual cutter armassemblies 208(1)-208(5) via cutter arm hub end 1330. Similarly, triggerarm bearing 3712 receives actuator assembly ‘part c’ 1108.

Considered from one perspective, the cutter arm hub 3716 can be thoughtof as including a vertical mounting flange that can be fastened to ringgear assembly 212 (FIG. 5). The vertical mounting flange can beinterposed between a first horizontal portion and a second horizontalportion. For ease of explanation, these first and second horizontalportions may be thought of as being tubular in some configurations. Thefront shaft bearing 3708 can be positioned within the first horizontalportion while the set of cutter assembly bearings 3704(1)-3704(5) can bepositioned without or around the first horizontal portion.

The two shaft bearings 3710(1) and 3710(2) can be positioned within thesecond opposing horizontal portion. Trigger arm bearing 3712 can bepositioned without or around the second horizontal portion.

Drive Wheel Assembly Examples

FIGS. 39-41 collectively illustrate drive wheel assembly 202 in moredetail. FIG. 39 is a side elevational view of the drive wheel assembly.FIG. 40 is a front elevational view of drive wheel assembly 202. FIG. 41is an exploded perspective view of the drive wheel assembly.

In this case, drive wheel assembly 202 includes a drive wheel hub 3902,a drive wheel 3904, a drive wheel gear 3906, a first set of fasteners3908, and a second set of fasteners 3910. The first set of fasteners3908 serve to fasten the drive wheel gear 3906 to the drive wheel 3904.The second set of fasteners 3910 serve to fasten the drive wheel hub3902 to the drive wheel 3904.

Drive wheel hub 3902 is received in the back side of drive wheel hubassembly 532 (FIGS. 37-38). Specifically, the drive wheel hub can bereceived into, and isolated from, cutter arm hub 3716 by two shaftbearings 3710(1) and 3710(2).

The width of the combined drive wheel hub 3902 and drive wheel hubassembly 532 (as measured along the cutter shaft or y-reference axis)generally does not exceed the harvest width w₁ of an individualharvester apparatus as discussed relative to FIG. 1. From anotherperspective the combined width defines the harvest width that the cutterarm assemblies operate within and harvest.

The drive wheel hub 3902 is driven by mechanical energy that istransferred from the cutter shaft to the drive wheel assembly 202 viathe drive wheel hub 3902. Toward this end, in some implementations agroove 3912 is formed in drive wheel hub 3902. A corresponding groovecan be formed in the cutter shaft 120 (see FIG. 1). During assembly,when an individual harvesting apparatus is positioned at the appropriatepoint on the cutter shaft, the grooves can be aligned and an expandablekey can be inserted into the resulting space. The expanding key can beexpanded to fasten the drive wheel hub 3902 and the cutter shaft so thatrotation of the cutter shaft rotates the drive wheel hub and thereby thedrive wheel.

As mentioned above, drive wheel hub 3902 is driven by the cutter shaft.However, along the combined width, individual bearings 3704(1)-3704(5)can serve to isolate individual cutter arm assemblies 208(1)-208(5) fromone another and from the cutter shaft. Similarly, trigger arm bearing3712 can isolate the actuator assembly and the cutter arm hub can beisolated from the cutter shaft and the drive wheel hub 3902 by bearings3710(1) and 3710(2) interposed therebetween. Energy from the cuttershaft and drive gear can be selectively transferred to individual cutterarm assemblies, the cutter arm hub and the actuator assembly asdescribed below relative to FIGS. 42-67.

While specific components are illustrated and discussed, othercomponents that can achieve the selective harvest functionality can beutilized in alternative configurations.

Harvesting Examples

FIGS. 42-82 collectively illustrate interactions of previouslyillustrated components of harvester apparatus 122(18) during theharvesting process.

FIG. 42 shows harvesting apparatus 122(18) in a first position. FIG. 43shows an enlarged view of a portion 4202 of the harvesting apparatus.Similarly, FIGS. 44 and 45 show position 2 in the same manner. Likewise,FIGS. 46 and 47 show position 3, FIGS. 48 and 49 show position 4, FIGS.50 and 51 show position 5, FIGS. 52 and 53 show position 6, and FIGS. 54and 55 show position 7. The pattern changes at position 8 which is shownin FIGS. 56-58, position 9 is shown in FIGS. 59-61, and position 10 isshown in FIGS. 62-64. FIGS. 65-79 offer additional views and/or moredetail related to the discussion of positions 8-10. Position 11 is shownin FIGS. 80-82.

FIGS. 42-55 generally show an example of how cutter arm assemblies208(1)-208(5) can be selectively driven with energy from cutter shaft120 to harvest asparagus spears. In this case, cutter shaft 120 isturning in a counter-clockwise direction. The cutter shaft ismechanically connected to, and drives, drive wheel assembly 202 suchthat drive wheel gear 3906 is likewise turning in a counterclockwisedirection as indicated at 4204. Planetary gears 3402(1)-3402(5) engage,and can be driven by, drive wheel gear 3906 and as such are turning in aclockwise direction as indicated at 4302. Also, for orientationpurposes, the direction of travel 102 of the overall selective harvesterover the ground is shown on FIG. 42.

Returning specifically now to FIGS. 42 and 43, the first position ofharvester apparatus 122(18) can be thought of as being a ‘neutral’ or‘ready position’ awaiting a signal from sensor 126(18) (FIG. 1). In theneutral position, shock absorber piston 515 is retracted. Actuatorassembly 206 is at a forward-most position against the shock absorberpiston 515. Further, trigger pin 3004(1) engages trigger block 1134which functions to prevent cutter arm assembly 208(1) from movingforward (i.e., counter-clockwise). The remaining trigger pins3004(2)-3004(5) engage latch detents 922(1)-922(4) respectively. Thelatch detents function to prevent the respective cutter arm assemblies208(2)-208(5) from moving backwards (i.e. clockwise). Also, the cutterarm bumpers of adjacent cutter arms engage one another. For instance,trailing side cutter arm bumper 1326(2) of second cutter arm assembly208(2) engages leading side cutter arm bumper 1327(3) of third cutterarm assembly 208(3).

In the neutral position, while the planetary gears 3402(1)-3402(5) arebeing driven by the drive wheel gear 3906, the planetary gears are notengaging ring gear 508, advancing gear 1106, or timing gear 1124.Instead, the planetary gears 3402(1)-3402(4) are aligned with gap 1144and gearless regions 1142(1), 1142(2), and 1142(3), respectively. (Dueto space constraints on FIGS. 42 and 43 illustrated gearless regions1142(1), 1142(2), and 1142(3) are not designated with specificity, seeFIGS. 11-12). Similarly, planetary gear 3402(5) is aligned with a gap4304 between the ring gear 508 and timing gear 1124. Accordingly,despite being driven by drive wheel gear 3906, gears 3402(1)-3402(5) donot impart radial motion to their respective cutter arm assemblies208(2)-208(5) in the neutral position.

FIGS. 44-45 are similar to those of FIGS. 42 and 43 respectively exceptthat harvester apparatus 122(18) is now in a second position (i.e.,position 2). As with FIGS. 42 and 43, FIG. 45 shows a portion 4402 ofthe harvesting apparatus shown in FIG. 44. Position 2 occurs responsiveto sensor 122(18) (designated FIG. 1) detecting a harvestable asparagusspear. Upon detecting the harvestable asparagus spear the sensor sends asignal to solenoid assembly 908. The signal activates the solenoidassembly thereby moving trigger 1128 downward toward the cutter shaft120. The downward movement of the trigger includes the trigger block1134 and the trigger tooth 1136. This downward movement allows triggerpin 3004(1) to clear trigger block 1134. Further, trigger tooth 1136moves downward into gap 1144 sufficiently to engage teeth of planetarygear 3402(1). Recall that in position 1 planetary gear 3402(1) is beingdriven by the drive wheel gear 3906, but the planetary gear is spinningfreely in gap 1144. Now, in position 2 as the planetary gear 3402(1)engages trigger tooth 1136 the planetary gear imparts a counterclockwiseforce upon its cutter assembly 202(1).

FIGS. 46-47 are similar to those of FIGS. 42 and 43, respectively exceptthat harvester apparatus 122(18) is now in a third position (i.e.,position 3). As with FIGS. 42 and 43, FIG. 47 shows a portion 4602 ofthe harvesting apparatus shown in FIG. 46. In position 3, planetary gear3402(1) has pushed against trigger tooth 1136 sufficiently to movecutter arm assembly 208(1) forward (i.e., counterclockwise) to the pointwhere planetary gear 3402(1) engages teeth of advancing gear 1106. Theinteraction of planetary gear 3402(1) and advancing gear 1106 impart aforward force on cutter arm assembly 208(1) and a corresponding oppositerearward force on actuator assembly 206. Accordingly, cutter armassembly 208(1) continues to move forward. Actuator assembly 206 startsto move rearward and is aided by extension of spring loaded piston 515of shock absorber 514. At this point, in addition to planetary gear3402(1) engaging advancing gear 1106, the remaining planetary gears3402(2)-3402(5) engage teeth of timing gear 1124. Specifically,planetary gear 3402(2) engages geared region 1140(1) (the other gearedregions 1140(2)-1140(4) are not labeled in FIG. 47 due to spaceconstraints, but are labeled on FIGS. 11-12). This results in cutter armassemblies 208(1)-208(5) moving forward and actuator assembly 206 movingrearward.

FIGS. 48 and 49 are again similar to FIGS. 42 and 43 respectively exceptthat harvester apparatus 122(18) is now in a fourth position (i.e.,position 4). FIG. 49 shows a close-up view as indicated at 4802. In thefourth position, rearward movement of the actuator assembly 206 isstopped by rear bumper 512(2). At this point since the actuator assembly206 cannot move further in the clockwise direction, the planetary gears3402(1)-3402(5) can be thought of as pushing against a fixed object. Assuch, the planetary gears can accelerate their respective cutter armassemblies 208(1)-208(5) to full speed in the counter-clockwisedirection.

To summarize, in this configuration, as a result of receiving a signalfrom the sensor, actuator assembly 206 gradually accelerates the set ofcutter arm assemblies 208(1)-208(5) as indicated in positions 2-4.

FIGS. 50 and 51 are again similar to FIGS. 42 and 43 respectively exceptthat harvester apparatus 122(18) is now in a fifth position (i.e.,position 5). FIG. 51 shows a close-up view as indicated at 5002. In thefifth position, planetary gears 3402(4)-3402(5) disengage from teeth ofthe timing gear 1124. Specifically, planetary gear 3402(5) movesclockwise from geared region 1140(4) into gap 1142(3). Similarly,planetary gear 3402(4) moves clockwise from geared region 1140(3) intogap 1142(2). Once the planetary gears 3402(4)-3402(5) disengage from thegeared regions there is no further radial force imparted upon respectivecutter arm assemblies 208(4)-208(5) in the counter-clockwise direction.

FIGS. 52 and 53 are again similar to FIGS. 42 and 43, respectivelyexcept that harvester apparatus 122(18) is now in a sixth position(i.e., position 6). FIG. 53 shows a close-up view as indicated at 5202.In the sixth position, planetary gear 3402(1) of cutter arm assembly208(1) engages ring gear 508 as indicated at 5302. As such, theplanetary gear 3402(1), driven by drive wheel gear 3906 and pushesagainst fixed ring gear 508. Accordingly, planetary gear 3402(1)continues to move cutter arm assembly 208(1) in a counter-clockwisedirection.

Further, in the sixth position, planetary gear 3402(3) of cutter armassembly 208(3) disengages from teeth of the timing gear 1124.Specifically, planetary gear 3402(3) moves clockwise from geared region1140(2) into gap 1142(1).

Further still, recall that individual planetary gears 3402(1)-3402(5)include a brake portion 3416 (see FIGS. 6-8). The brake portion isconfigured to engage brake rail 516. In position 6, the brake portionsof planetary gears 3402(2)-3402(5) engage brake rail 516 which begins agradual de-acceleration process of respective cutter arm assemblies208(2)-208(5). Further, trigger pin 3004(2) (not designated due to spaceconstraints) contacts trigger block 1134 as indicated at 5304 (thetrigger pin and trigger block are not designated in these FIGS. due tospace constraints). Recall that the trigger block is a component of theactuator assembly 206. Further, recall that the actuator assembly is ina rearward position. The trigger pin 3004(2) contacts trigger block 1134and (along with the above mentioned brake rail contact) moves theactuator assembly 206 forward (i.e., counter-clockwise). The actuatorassembly, of course, has mass and thereby inertia. Accelerating theactuator assembly forward causes deceleration (i.e., slowing) of cutterarm assemblies 208(2)-208(5).

FIGS. 54 and 55 are again similar to FIGS. 42 and 43, respectivelyexcept that harvester apparatus 122(18) is now in a seventh position(i.e., position 7). FIG. 55 shows a close-up view as indicated at 5402.In position 7, cutter arm assemblies 208(2)-208(5) continue theirdeceleration as they move actuator assembly 206 forward until itcontacts front bumper mount assembly 512(1).

The front bumper mount assembly 512(1) can be compressible to providesome shock absorption or ‘cushion’. Lacking another signal from thesensor to solenoid assembly 908, forward movement of cutter armassemblies 208(2)-208(5) and actuator assembly 206 stops once the frontbumper mount assembly 512(1) is compressed. Considered another way,lacking another signal (caused by sensing another harvestable asparagusspear in close proximity to the first) within a predetermined period oftime the second and subsequent cutter arm assemblies are decelerated andstopped.

Also, at this point, rearward travel of trigger pins 3004(3)-3004(5) islimited by latch detents 922(1)-922(3), respectively. Alternatively, ifthe sensor senses another harvestable asparagus spear and sends anothersignal to the solenoid assembly 908, then forward movement of theactuator assembly 206 is stopped by the front bumper mount assembly512(1), but the cutter assemblies can continue their forward movement asdescribed above relative to FIGS. 42-53 except that each cutter armassembly 208(2)-208(5) has moved up one position or place.

Stated another way, as cutter arm assembly 208(1) moves away from theactuator assembly 206 around ring gear 508, the process can be repeatedexcept that cutter arm assembly 208(2) moves forward to take theposition or place previously occupied by cutter arm assembly 208(1).Similarly, cutter arm assembly 208(3) moves forward to take the positionor place previously occupied by cutter arm assembly 208(2), cutter armassembly 208(4) moves forward to take the position or place previouslyoccupied by cutter arm assembly 208(3) and cutter arm assembly 208(5)moves forward to take the position or place previously occupied bycutter arm assembly 208(4). The place or position previously occupied bycutter arm assembly 208(5) is temporarily vacant until cutter armassembly 208(1) completes its journey around ring gear 508 describedbelow.

In summary, after the acceleration of positions 2-4, the performance ofactuator assembly 206 depends on receipt of a subsequent signal(s). Ifno subsequent signal is received, the actuator assembly 206 graduallydecelerates and stops the remaining cutter arm assemblies 208(2)-208(5).Once the remaining cutter arm assemblies 208(2)-208(5) come to a stop,the process can be repeated as in position 1 with each of these cutterassemblies moving up one place. Alternatively, if a subsequent signal(s)is received while remaining cutter arm assemblies 208(2)-208(5) arestill moving, these remaining cutter arm assemblies can be reacceleratedby the actuator assembly 206.

FIGS. 42-55 when considered collectively describe an example of a clutchor control assembly that is configured to control individual cutter armassemblies 208(1)-208(5) based upon signals received from the sensor. Inthis case, actuator assembly 206 functions as the clutch assembly. Inthis example, mechanical force for driving the cutter arm assemblies208(1)-208(5) is provided by cutter shaft 120 via the drive gear 3906.Actuator assembly 206 functions to selectively impart radial motion tocutter arm assemblies 208(1)-208(5) with the mechanical force based uponsignals received from sensor 126(18) (FIG. 1). For instance, position 1shows the cutter arm assemblies 208(1)-208(5) in a neutral or readyposition where the actuator assembly is not imparting radial motion tothe cutter assemblies.

Positions 2-4 show actuator assembly 206 imparting radial motion to thecutter arm assemblies 208(1)-208(5) via activation of solenoid assembly908. In Positions 5-7 cutter arm assembly 208(1) continues its radialmotion and leaves the control of actuator assembly 206, while theremaining cutter arm assemblies 208(2)-208(5) are individually decoupledfrom the mechanical force of the cutter shaft. During this period,either the actuator assembly 206 receives another signal and againimparts radial motion on cutter arm assemblies 208(2)-208(5), oractuator assembly 206 returns them to the neutral or ready position.

Further, actuator assembly 206 offers two noteworthy features in themanner in which it imparts or does not impart radial motion to thecutter arm assemblies 208(1)-208(5). First, upon receipt of a sensorsignal, actuator assembly 206 imparts radial motion upon multiple cutterarm assemblies. For instance, in position 2, the actuator assembly 206imparts radial motion upon all of the cutter arm assemblies208(1)-208(5) under its control.

Imparting motion to multiple cutter arm assemblies rather than just theleading cutter assembly 208(1) can allow harvesting apparatus 122(18) toharvest relatively closely spaced asparagus spears. For instance,consider a scenario where the sensor detects a first asparagus spear andthen another asparagus spear a couple of inches later. Upon detection ofthe first spear a signal is sent to the actuator assembly's solenoidassembly 908 (i.e., position 2). In this configuration, the actuatorassembly causes all of the cutter arm assemblies 208(1)-208(5) to beginmoving radially. The first cutter arm assembly 208(1) continues movingradially to harvest the first asparagus spear. When the second signal isreceived, the second cutter arm assembly is already moving radially. Asecond activation of the solenoid assembly can send the second cutterarm assembly 208(1) after the first cutter assembly 208(1) with lessdelay than if the second cutter assembly 208(2) had been stationary whenthe second sensor signal was received by the actuator assembly 206.Stated another way, since the second cutter arm assembly 208(2) isalready moving when the second sensor signal is received, the secondcutter arm assembly 208(2) can be separated from the first cutter armassembly 208(1) by fewer radians than if the second cutter arm assembly208(2) had been stationary. This example is explained in the context oftwo asparagus spears sensed in close proximity to one another. However,this feature is also applicable to situations where 3, 4, or 5 or moreasparagus spears are sensed in close proximity to one another.

Another feature of interest that is offered by actuator assembly 206 isthe rate of acceleration and deceleration of the cutter arm assemblies208(1)-208(5) during operation. Relatively sudden acceleration and/ordeceleration can result in components experiencing high peak forces.High peak forces contribute to equipment failure, especially overmultiple thousands of cycles. In contrast, actuator assembly 206 offersrelatively gradual acceleration and deceleration of the cutter armassemblies 208(1)-208(5). For instance, as described above, accelerationof cutter arm assemblies 208(1)-208(5) begins in position 2. The peakacceleration of the cutter arm assemblies 208(1)-208(5) is lessened inthat in order to move forward in a counter-clockwise direction, theyexert a force on the actuator assembly 206 thereby pushing it backwards.Not until position 4 where the actuator assembly 206 is stopped fromfurther rearward travel do the cutter arm assemblies 208(1)-208(5)experience full acceleration. Stated another way, the cutter armassemblies 208(1)-208(5) can be gradually accelerated between positions2 and 4.

Similarly, deceleration of the cutter arm assemblies 208(2)-208(5)begins when their respective planetary gears 3402(2)-3402(5) engagebrake rail 516 of actuator assembly 206. The trigger pin 3004(2)contacts trigger block 1134 and moves the actuator assembly 206 forward(i.e., counter-clockwise). Accelerating the actuator assembly forwardcauses deceleration (i.e., slowing) of the cutter arm assembly 208(2)(and thereby cutter arm assemblies 208(3)-208(5)).

In position 7, cutter arm assemblies 208(2)-208(5) continue theirdeceleration as they move actuator assembly 206 forward until itcontacts and compresses front bumper mount assembly 512(1). Thus,actuator assembly 206 offers an example of a clutch mechanism thatselectively and independently controls the cutter arm assemblies208(1)-208(5) in a manner that allows successful harvesting ofrelatively closely spaced asparagus spears while decreasing peak forcesupon the cutter arm assemblies 208(1)-208(5).

FIGS. 56-58 show harvester apparatus 122(18) in an eighth position(i.e., position 8). FIG. 56 is a perspective view of position 8, FIG. 57is a side elevational view, and FIG. 58 is a front elevational view ofposition 8. Recall from FIGS. 5-8 that ring gear assembly 212, includesa cam 504 that varies in thickness along its circumference. Furtherrecall from FIGS. 13-17 that cutter arm assembly 208(1) includes a camfollower 1342.

The cam follower 1342 follows the thickness of the cam as cutter armassembly 208(1) radially progresses around the circumference. As the camfollower 1342 experiences increasing thickness of region 548 of cam 504,the cam forces the cam follower 1342 outward as indicated by arrow 5602.This outward movement of cam follower 1342 is transferred through thepushrod's ball end linkage bottom 1324 to opening wedge 1314. Theoutward pressure on the opening wedge pushes the opening wedge againstcontact structure 1341. A curved surface of the opening wedge contactsand forces opening bearing 1344 (and hence spring arm 1306) to move at aright-angle to arrow 5602 as indicated at 5604. Arrow 5604 extendsparallel to the y-reference axis. Opening wedge 1314 also pushes againstthe contact structure 1341 of the cutter arm causing the cutter arm toopen in an opposite direction as the spring arm. Thus, the force fromcam 504 is translated in a manner that causes cutter assembly 1304 andspring arm assembly 1306 to move away from one another (i.e., open) asindicated at 5604.

Thus, position 8 shows that the cutter assembly 1304 and spring armassembly 1306 are opened to a width w₁ (introduced FIG. 1) as cutter armassembly 208(1) approaches the harvest zone. This explanation can beapplied to the remaining cutter assemblies 208(2)-208(5). Thus, each ofthe cutter assemblies is capable of harvesting asparagus spears withinwidth w₁. In summary, cam 504 and cutter arm assembly 208(1) function toopen the cutter assembly 1304 and spring arm assembly 1306 and hold themopen so that asparagus spears in the harvest zone pass between thecutter assembly 1304 and spring arm assembly 1306 rather than on theoutside of one of them.

Note further, that at this point cutter arm spring 1812 resilientlybiases cutter knife 1806 in an outward direction (i.e., away from cuttershaft 120). This aspect will be discussed in more detail below relativeto position 9.

FIGS. 59-61 show harvester apparatus 122(18) in a ninth position (i.e.,position 9). FIG. 59 is a perspective view of position 9, FIG. 60 is aside elevational view, and FIG. 61 is a front elevational view ofposition 9. For orientation purposes, the surface of the ground or soiland a harvestable asparagus spear 134 are shown in FIG. 60 along withthe direction of movement 102 of the selective harvester. These featuresare not shown relative to FIGS. 59 and 61 to avoid obstructingcomponents of cutter arm 208(1).

In position 9, the sensed asparagus spear 134 is just about to passbetween the cutter assembly 1304 and spring arm assembly 1306. At thispoint, cam 504 transitions from thicker region 548 to thinner region550. Accordingly, the cam follower 1342 is no longer forced outward andthus the cutter assembly 1304 and spring arm assembly 1306 are no longerheld ‘open’ as in position 8 described above. This can be thought of asa ‘floating’ position.

In this floating position, the cutter assembly 1304 and spring armassembly 1306 can begin to close toward each other until one or bothcontact the asparagus spear. Further, the cutter assembly 1304 andspring arm assembly 1306 can swing independently of one another relativeto (i.e., parallel to) the y-reference axis. In this case, the cutterassembly 1304 is hingedly attached to the arm mount master 1302 (seeFIGS. 13-17). Spring arm assembly 1306 is also hingedly attached to thearm mount master 1302 (see FIGS. 13-17). Thus, the cutter assembly 1304and the spring arm assembly 1306 can each move or swing inwardlyindependently of one another. If one of the cutter assembly 1304 and thespring arm assembly 1306 contacts the asparagus spear, the other cancontinue to move inwardly until also contacting the spear. Thus, theasparagus spear can be grasped between the cutter assembly 1304 and thespring arm assembly 1306. Specifically, the asparagus spear is graspedbetween pad 1830 of cutter assembly 1304 and pad 2216 of spring armassembly 1306 (see FIGS. 18-25).

Recall that in the discussion of FIG. 1 a distance 132 between thesensed area and the harvesting apparatus was introduced. The discussionrelative to FIGS. 2-61 illustrate that a rotation of the cutter shaftand/or the gear ratios selected for the above components can allow thecutter arm assembly to be rotated at a rate so that the sensed asparagusspear is grasped between the pads 1830 and 2216 below the cutter shaft.Stated another way, upon sensing an asparagus spear, the time that theselective harvester takes to travel distance 132 matches the time that acutter arm assembly takes to rotate to a position proximate to the soiland the spear.

FIGS. 62-64 show harvester apparatus 122(18) in a tenth position (i.e.,position 10). FIG. 62 is a perspective view of position 10, FIG. 63 is aside elevational view, and FIG. 64 is a front elevational view ofposition 10. In a similar manner to position 9, asparagus spear 134, theground surface and the direction of movement 102 are shown relative toFIG. 63.

In position 10, the sensed asparagus spear 134 should now be grasped(and/or in the process of being grasped) between the cutter assembly1304 and spring arm assembly 1306. At this point, the cutter assembly1304 and spring arm assembly 1306 are then locked together as they graspthe spear. Specifically, cam follower 1342 contacts locking cam 520. Thelocking cam forces the cam follower upward or inward as indicated byarrow 6202. Inward movement of the cam follower is transferred throughpushrod 1321 to opening wedge 1314. Thus, the inward or upward movementof the cam follower 1342 pulls upwardly on the opening wedge 1314. Theopening wedge then forces locking wedge 1320 upward. In this view thelocking wedge is just starting to engage locking bearing 1346. As thelocking wedge 1320 moves upward the front surface of the locking wedgeserves to block the inward movement of the locking bearing 1346 andthereby locks the cutter assembly 1304 and spring arm assembly 1306together.

Further, as cutter assembly 208(1) continues to move radially, cutterknife 1806 begins to contact the surface of the soil (and may passthrough the surface into the soil). Recall from the discussion ofposition 8 that, in some implementations, cutter arm spring 1812resiliently biases cutter knife 1806 in an outward direction (i.e., awayfrom cutter shaft 120). Contact with the soil surface can overcome thisresilient bias and force the cutter knife upward or inward toward thecutter shaft. Shortly thereafter, and while in the upward position, thecutter knife can contact and sever the asparagus spear 134 at or belowthe soil surface. The discussion of this aspect will continue relativeto position 11.

FIGS. 65-79 show slightly different views of harvester apparatus 122(18)in an attempt to illustrate features that might not be apparent in theprevious FIGS. For ease of discussion, FIGS. 65-67 can be thought of asshowing cutter assembly 208(1) at the advanced stages of position 8described above. FIGS. 68-70 are similar to position 9. FIGS. 71-73 arebetween positions 9 and 10. FIGS. 74-76 are similar to early position10. FIGS. 77-79 are similar to position 10. Note, that direction ofmovement 102 of the selective harvester is again provided fororientation purposes.

FIGS. 65-67 show a cam driven open position where cutter assembly 1304and spring arm assembly 1306 are held away from one another by cam 504.Pushrod 1321 transfers force from cam follower 1342 to opening wedge1314. This force causes spring arm 1306 to open. Similarly, the openingwedge is forced against contact structure 1341. This outward forceovercomes a resilient inward bias created by spring 6502 and causes thespring to extend. At this point, neither of the cutter assembly 1304 andspring arm assembly 1306 has contacted asparagus spear 134.

FIGS. 68-70 show cam follower 1342 disengaging from cam 504 and startingto ‘float’. Thus, force is no longer applied by the opening wedge 1314to overcome the inward bias of spring 6502. As such, the spring startsto pull the cutter assembly 1304 and spring arm assembly 1306 toward oneanother. In this example, inward movement of spring arm assembly 1306 isstopped by contact with asparagus spear 134 while cutter assembly 1304continues its inward movement.

In this illustrated floating position, there is little or notension/force on push rod 1321 so the opening wedge 1314 is free to moveor can be considered ‘loose’. Stated another way, each of cutterassembly 1304 and spring arm assembly 1306 can move independently of theother, parallel to the y-reference axis. Such a configuration can allowthe cutter assembly 1304 and the spring arm assembly 1306 to ‘center’ onthe asparagus spear 134 rather than upon a preset location. In summary,in this example, cutter assembly 1304 and the spring arm assembly 1306move toward one another until spring arm assembly 1306 contactsasparagus spear 134. The asparagus spear stops spring arm assembly 1306(relative to the y-reference axis). The cutter assembly 1304 is free tocontinue its inward movement until it too contacts the asparagus spear.Considered from another perspective, cutter assembly 208(1) is free topivot relative to the y-reference axis such that the cutter assembly cancenter itself upon the asparagus spear 134.

Continuing with the float position, FIGS. 71-73 show the cutter assembly1304 has continued its inward movement until the asparagus spear 134 isgrasped between the spring arm assembly 1306 and cutter assembly 1304via the force imparted by spring 6502. Specifically, the asparagus spearis grasped between pad 2216 of the spring arm assembly 1306 and pad 1830of the cutter assembly 1304. (Of course, other implementations canutilize other contact elements besides pads). The pads can rotate toreduce or avoid rubbing or damaging the asparagus spear. In someimplementations, the harvester apparatus 122(18) can be thought of asbriefly rotating around an axis passing through the pads parallel to thecutter shaft (i.e., parallel to the y-reference axis). For instance,such an axis can extend into and out of the printed page upon whichFIGS. 71-73 appear at point 7102.

FIGS. 74-76 are similar to FIGS. 71-73 except that the cam follower 1342is engaging or contacting locking cam 520. The locking cam forces thecam follower upward or inward. This upward movement is transferreddownward via pushrod 1321 to lock the spring arm assembly 1306 andcutter assembly 1304 together around the asparagus spear.

FIGS. 77-79 show a subsequent point where the pads 1830 and 2216continue to rotate around the axis indicated at point 7102 until thecutter knife 1806 severs or cuts the asparagus spear 134. The cutterknife 1806 is configured to absorb impact imparted by contact with theground. In this case, the cutter knife is spring loaded via cutter armspring 1812. As discussed above, and in the discussion below relative toposition 11, this spring loaded feature can also offer other potentialadvantages. As will be described in more detail below relative to FIGS.89-91, the shape of the cutter knife can also absorb impact energy.

FIGS. 80-82 show position 11. Recall that in position 10, the camfollower 1342 was contacting locking cam 520 which kept the spring armassembly 1306 and cutter assembly 1304 locked together around theasparagus spear. Also recall that, as the cutter knife contacted thesoil in position 10, the cutter knife 1806 was forced upward and thecutter arm spring 1812 was compressed. Subsequently, between positions10 and 11 the cutter knife ceases contact with the soil and cutter armspring 1812 again resiliently biases the cutter knife outward. Theasparagus spear 134 is locked between the pads of the cutter assembly1304 and the spring arm assembly 1306 so the outward movement of thecutter knife 1806 separates the cutter knife from the asparagus spear.

Further, between position 10 and position 11 the cutter arm assembly208(1) proceeds to a point where the cam follower 1342 disengages fromthe locking cam 520. In position 11, the cutter arm assembly 208(1)proceeds to a point where the cam follower is forced outward by a wideor thick portion 552 of cam 504. The cam forces the cam followerdownward and thereby opens the spring arm assembly 1306 and cutterassembly 1304 in a similar manner to that explained above relative toFIGS. 56-58. This motion then releases the asparagus spear 134 in acollection zone (not specifically designated). As mentioned above,cutter knife 1806 has already moved away from the asparagus spear, soany tendency of the asparagus spear to stick to the cutter knife isreduced or eliminated. Otherwise, fibers of the asparagus spear may bestuck to the cutter knife and cause the spear to dangle from the cutterknife rather than falling away. This knife movement may be more readilyapparent from FIGS. 83-88 discussed below.

In the collection zone, the released asparagus spear 134 can fall into astrategically placed collection mechanism (not specifically shown). Thecollection mechanism can simply be a box placed behind the cutter armassemblies 208. In another case, the collection mechanism may have aconveyer mechanism, such as a conveyer belt that moves the harvestedasparagus spears to another region of the selective harvester or off ofthe selective harvester.

Knife Examples

FIGS. 83-88 collectively illustrate knife positions and movement duringthe harvesting process relative to cutter assembly 1304. FIGS. 83, 85,and 87 show cutter knife 1806 in a downwardly biased orientationproduced by cutter arm spring 1812 acting upon the cutter knife. FIGS.84, 86, and 88 show the same orientations as FIGS. 83, 85, and 87,respectively except that the downward bias of cutter arm spring 1812 hasbeen overcome by contact with the soil which can temporarily force thecutter knife upward by a distance Δz.

FIGS. 89-95 show additional cutter knife features. FIGS. 89-91 aresimilar in orientation to FIGS. 87-88 but focus upon the cutter knife1806. In this case, as indicated in FIG. 90, unless acted upon by thesoil, in some implementations, a cutting portion 8902 of the cuttingknife is not parallel with the surface of the soil. Instead, the cuttingportion can be thought of as forming an acute angle α relative to thesoil or an obtuse angle β relative to a vertical portion 8904 of thecutting knife (and/or the cutter arm assembly generally). Contact withthe soil surface during the harvesting process can flex or bend thecutter knife such that the cutting portion 8902 is parallel with theground and/or forms a right angle β with the vertical position 8904 whencontacting and severing asparagus spear 134. This feature can allow thecutter knife 1806 to absorb shock associated with contacting the soil.Further, as can be evidenced from FIG. 91, upon cycling upward away fromthe soil, cutter knife 1806 can return to the original configurationdescribed relative to FIG. 89. Accordingly, since the asparagus spear isgrasped in a manner described above, this feature allows the cutterknife to pull away from the harvested asparagus spear 134 aftercessation of contact with the soil. Stated another way, the spear isheld by the pads and as contact with the ground ceases the cutter knifecan flex away and create separation from the base of the spear. Itshould be recognized that other cutter knife configurations can be usedin various implementations. Further, while the above discussiondescribes features which allow the cutter knife to absorb impact fromcontacting the soil, the cutter knife does not need to contact the soilfor the harvester apparatus to function.

FIG. 92 shows another view of the cutting portion 8902 of cutter knife1806. FIG. 92 is a cross-sectional view through cutter knife 1806parallel to the xz-reference plane as indicated in FIG. 85. In thisconfiguration, a leading edge 9202 is at an upper surface 9204 of thecutting portion. An angled cutting surface 9206 extends from the leadingedge back down to a lower surface 9208. Upon contact with the soilsurface and/or upon passing into the soil, an upward force 9210 iscreated by the soil that can reduce a tendency of the cutting portion to‘dive’ or ‘plow’ deeper into the soil as the cutting knife moves throughthe soil as indicated by arrow 9212. While some implementations can useother cutter knife configurations, this configuration can reduce stresson cutting knife 1806 and/or other components of the harvestingapparatus.

FIGS. 93-95 show three different implementations of lower portion 8902in a view similar to the view of FIG. 83. For ease of explanation, theselower portions are designated as lower portion 8902(1), 8902(2), and8902(3), in FIGS. 93-95 respectively. Similarly, leading edges aredesignated as 9202(1), 9202(2), and 9202(3), respectively.

In some implementations, the leading edge can be parallel to the cuttershaft or the y-reference axis. One such implementation is shown in ghost(dashed lines) relative to FIG. 93 with the leading edge designated as9202(4). Other implementations can have the leading edge at an obliqueangle γ relative to the cutter shaft or the y-reference axis. Anglingthe leading edge can facilitate the asparagus spear and leading edgemoving relative to one another upon contact. This movement, which may bethought of as lateral movement, can facilitate a cutting action of theleading edge on the asparagus spear. The base of an asparagus spear canbe very fibrous and as such difficult to cut cleanly. Further, cuttingedge 9202(1) is smooth, while cutting edges 9202(2) and 9202(3) areserrated. The serrations can further aid in cutting the fibrousasparagus spear. Further still, while cutting edges 9202(1) and 9202(2)are generally linear, cutting edge 9202(3) is curvilinear (a linear line9502 is provided for reference). In this particular instance, cuttingedge 9202(3) can be considered convex, though other configurations canbe employed. The combination of serrations and a curvilinear surface canfurther facilitate cleanly cutting the fibrous asparagus spear duringharvesting.

Conclusion

The above description goes into great detail regarding the structure ofspecific implementations. These structures offer examples foraccomplishing the selective harvesting functionality described andclaimed herein. For instance, functionality offered by the presentlydescribed concepts allows for sensing asparagus spears and selectivelyharvesting individual spears while leaving other spears relativelyunharmed. As the selective harvester travels over an asparagus field,the selective harvesting functionality can have the capacity toselectively harvest individual harvestable spears across a width of theselective harvester. Some implementations accomplish this functionalityutilizing a set of serially arranged harvesting apparatus. Individualharvesting apparatus can have the capacity to selectively harvestmultiple closely-spaced harvestable asparagus spears. Otherimplementations can utilize variations of the described structuresand/or different structures to accomplish the selective harvestingfunctionality described herein.

The invention claimed is:
 1. A harvester, comprising a harvestingapparatus that defines an overall width and that includes a hub-bearingassembly and a set of independently controllable cutter arm assembliesthat do not exceed the overall width, wherein each of the independentlycontrollable cutter arm assemblies is configured to harvest across anentirety of the overall width.
 2. The harvester of claim 1, wherein thehub-bearing assembly includes a drive hub configured to engage a drivencutter shaft.
 3. A device, comprising a cutter arm hub configured to bepositioned on a cutter shaft and that includes a vertical mountingflange interposed between a first horizontal portion of the cutter shaftand a second horizontal portion of the cutter shaft; a set of cutterassembly bearings positioned on an outer surface of the first horizontalportion and an inner shaft bearing positioned on an inner surface of thefirst horizontal portion; and, another inner bearing positioned on aninner surface of the second horizontal portion and an arm bearingpositioned over the another inner bearing on an outer surface of thesecond horizontal portion.
 4. The device of claim 3, wherein only theinner shaft bearing of the device is configured to contact the cuttershaft upon which the device is positioned.
 5. The device of claim 3,wherein the another inner bearing is configured to receive a drive wheelhub that is configured to be driven by the cutter shaft upon which thedevice is positioned.